representative sample of a soil on old till deposits on the valley sides above Lake Vanda; also likely to be a totally undisturbed reference site for contamination studies
Description:
on a sloping glacial bench surface on the north side of Wright Valley, above Lake Vanda and approximately 2km due north of Vanda Station
Altitude:
500 m
Aspect:
S
Slope:
11 °
Location Data
Observer
IBC
GGC
GPS
No
Latitude Longitude DMS
77° 30.54' S 161° 39.36' E
77° 0.0' S 161° 40.0' E
Latitude Longitude DD
-77.50900 161.65600
-77.000 161.667
Latitude longitude precision DD
0.00008 0.00008
0.008 0.008
Locality
Wright Valley to the north of Vanda Station
Survey
not recorded
Climate
Soil climate zone:
central mountain
Estimated mean annual temperature:
-23
°C
Frozen ground depth:
30 ~
Frozen type:
dry frozen
Frozen comment:
~30
Geology
Geological setting:
the deposits on the valley walls in the vicinity of Lake Vanda are commonly described as scree. Close examination showed that there is a series of distinct westward sloping benches (glacial retreat lines) and that the deposits comprise a wide variety of rocks, some of which are basement rocks similar to those occurring down-valley. These deposits are therefore thought to be the deposits from early up-valley glacial advances with relatively minor amounts of detritus originating directly from the Olympus Range. Pale grey till underlies most of the surficial material and may be Peleus Till.
Patterned ground:
Surface weathering or surface features:
moderate staining and oxidation of surface clasts which also exhibit rounding, ventifaction and cavernous weathering
Soil
Soil parent material:
thin intermittent drift over older pale fine textured drift from basement rocks, granites, dolerite and sandstone
xerous; the soil surface is occasionally moistened by summer snowfall;
Biological activity:
Profile Description
Horizon
Depth
Description
705a
-1
–
0
cm
surface pebbles, granules and coarse sand; subangular to subrounded; small particles with some weak staining with larger clasts showing more distinct staining,
705b
0
–
3
cm
light yellowish brown (10YR 6/4) gravelly pebbly granular sand; moderately cohesive with a distinct surface crust; rock particles subangular to subrounded and weakly stained; distinct boundary,
705c
3
–
15
cm
light yellowish brown (10YR 6/4) pebbly granular sand; loose; rock particles subangular to subrounded and weakly stained; irregular boundary,
705d
15
–
20
cm
pale yellow to light yellowish brown (2.5Y 7/4-6/4) gravelly silty sand; moderately cohesive; rock particles mainly angular to subangular with some granular clasts disaggregated and partly oxidised; distinct boundary,
705e
20
–
32
cm
pale yellow to light yellowish brown (2.5Y 7/4-6/4) gravelly silty sand; firm to moderately cohesive; salt accumulations diffused through the horizon; rock particles angular to subangular and unstained; distinct boundary,
705f
32
–
55
cm
pale olive (5Y 6/3) gravelly silty sand with some medium boulders; weakly cohesive; rock particles subangular to angular and unweathered; indistinct boundary,
705g
55
–
85
cm
pale olive (5Y 6/3) silty to sandy pebbly to cobbly gravel; moderately cohesive; rock particles angular to subangular with occasional clasts crumbled; diffuse boundary,
705h
85
–
100
cm
pale yellow (5Y 7/3) silty to sandy pebbly to cobbly gravel; moderately cohesive; rock particles angular to subangular and unweathered; diffuse boundary, on pale till.